US2167122A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for heating
Assignee: METCALF Manufacturing CO
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Filing: 1938-04-18
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Granted: 1939-07-25
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Expires: 1958-04-18
Abstract
No abstract record available.
Inventors
- 👤 Howard H Metealf
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 23:15
CPC Classifications
F; F24; F24H; F24H3/00; F24H3/02; F24H3/04; F24H3/0405; F24H3/0411
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1942-07-24 | 1943-01-23 | 1943-07-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1946-07-24 | 1947-01-23 | 1947-07-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1950-07-24 | 1951-01-23 | 1951-07-25 | $7700.00 | Window Closed / Lapsed |